A number of Gram-negative bacterial proteins, mostly found in pathogens and associated with virulence, contain a conserved C-terminal domain that integrates into the outer membrane and enables the N-terminal region to be delivered across the membrane. This C-terminal autotransporter domain is about 400 amino acids in length and includes the aromatic amino acid-rich OMP signal, typically ending with a Phe or Trp residue, at the extreme C-terminus. [Protein fate, Protein and peptide secretion and trafficking, Cellular processes, Pathogenesis]
Jiyao W et al.(2023). "The conserved domain database in 2023.",